The present invention relates generally to pancake type slip rings, and more particularly, to an article and a method for manufacturing a pancake type slip ring.
Pancake type slip rings are typically manufactured by plating a dielectric substrate with an electrically conductive material such as copper. Using photo lithographic techniques, the electrically conductive plating is etched to form a plurality of conductive rings. For example, the conductive rings can be formed as disclosed in U.S. patent application Ser. No. 09/246,098, filed Feb. 8, 1999 entitled xe2x80x9cELECTRICAL SLIP RING HAVING A HIGHER CIRCUIT DENSITYxe2x80x9d (pending) and U.S. Pat. No. 5,901,429 issued May 11, 1999, entitled xe2x80x9cMETHOD OF MANUFACTURING COMPOSITE PANCAKE SLIP RING ASSEMBLYxe2x80x9d, both of which are incorporated herein by reference in their entirety.
The disadvantage with such arrangements is the high cost to manufacture the conductive rings used in the pancake type slip ring. Thus, there is a need in the art for a conductive or a pancake type slip ring in which the cost of manufacturing the pancake type slip ring has been substantially reduced.
It is, therefore, an object of the present invention to provide a method for manufacturing a rotor for a pancake type slip ring which is economical to produce, cost effective to manufacture and reliable in operation.
It is a further object of the present invention to manufacture a flat rotor for a pancake type slip ring in which the conductive rings have been stamped in a process before being bonded to a dielectric layer.
The present invention advantageously provides a cost effective flat rotor for a pancake type slip ring. A flat copper sheet is stamped into a corrugated shape having concentric V-rings. The corrugated stamped copper foil sheet is bonded using a bonding agent to a dielectric layer. Multiple concentric V-grooves are formed by separating the V-rings, for example, by machining the V-rings at an apex thereof in order to form separate electrical circuits. A corresponding plurality of holes extends through each concentric ring and through the dielectric layer from the first side through the second side. A conductive material is placed in each of the plurality of holes to electrically connect each concentric ring to the second side. Holes are drilled through each of the separate electrical circuits to electrically connect each of the V-rings to a separate foil trace on the back side of the dielectric layer.
These and other objects of the present invention are achieved by a method of manufacturing a flat rotor portion for an electrical slip ring. The method includes a copper foil and bonding the copper foil sheet to a dielectric layer. The grooves are separated to form separate electrical circuits.
The foregoing objects are also achieved by a rotor portion for a pancake type slip ring which comprises a dielectric layer having a first side and a second side. A plurality of concentric rings are each adjacent the first side of dielectric layer. A corresponding plurality of holes extends through each concentric ring and through the dielectric layer from the first side through the second side. A conductive material is placed in each of the plurality of holes to electrically connect each concentric ring to the second side.
Still other objects and advantages of the present invention will become readily apparent to those skilled in the art from the following detailed description, wherein the preferred embodiments of the invention are shown and described, simply by way of illustration of the best mode contemplated of carrying out the invention. As will be realized, the invention is capable of other and different embodiments, and its several details are capable of modifications in various obvious respects, all without departing from the invention. Accordingly, the drawings and description thereof are to be regarded as illustrative in nature, and not as restrictive.